Drug Levels and Effects:

Summary of Use during Lactation:

Chasteberry (Vitex agnus-castus) is the fruit (berries) from the chaste tree. The berries contain essential oils (e.g., limonene, sabinene, 1,8-cineole [eucalyptol]), iridoid glycosides (e.g., agnoside, aucubin), diterpines (e.g., vitexilactone, rotundifuran), and flavonoids (e.g., apigenin, castican, orientin, isovitexin). Some constituents, possibly the diterpene clerodadienols, bind to dopamine D2 receptors in the pituitary.[1] In low doses, chasteberry increases serum prolactin. Chasteberry is often used for irregularities of the menstrual cycle, infertility, premenstrual complaints, and cyclical breast pain.[2][3] It is also a purported galactogogue;[4][5][6] however, no scientifically valid clinical trials support this use. In fact, some evidence indicates that high doses of chasteberry decrease serum prolactin and might decrease lactation. Galactogogues should never replace evaluation and counseling on modifiable factors that affect milk production.[7]

No data exist on the safety and efficacy of chasteberry in nursing mothers or infants. In general, chasteberry is well tolerated. The most frequent adverse events are nausea, headache, gastrointestinal disturbances, menstrual disorders, acne, pruritus, and erythematous rash; however, all are mild and reversible.[8] Because of the lack of safety data and the possibility of lactation suppression, chasteberry should be avoided during lactation.[9]

Dietary supplements do not require extensive pre-marketing approval from the US Food and Drug Administration. Manufacturers are responsible to ensure the safety, but do not need to prove the safety and effectiveness of dietary supplements before they are marketed. Dietary supplements may contain multiple ingredients, and differences are often found between labeled and actual ingredients or their amounts. A manufacturer may contract with an independent organization to verify the quality of a product or its ingredients, but that does not certify the safety or effectiveness of a product. Because of the above issues, clinical testing results on one product may not be applicable to other products. More detailed informationabout dietary supplementsis available elsewhere on the LactMed Web site.

Drug Levels:

Maternal Levels.

Twelve nursing mothers who were19 weeks to 19 months postpartum ingested 100 mg of 1,8 cineole (eucalyptol) in the form of delayed-release capsules (Soledum-Klosterfrau Vertriebs GmbH, Germany) that release the drug in the intestine. Then they pumped 1 to 4 milk samples at the time they perceived the smell of eucalyptus on their breath which had been previously shown to be approximately concurrent. A total of 21 milk samples were obtained. Odor was rated by a panel of 3 to 5 experts as either smelling like eucalyptus or not. Fourteen of the samples had a distinct eucalyptus-like odor. Chemical analysis of the positive odor tests found 1,8-cineole in concentrations from 70 to about 2090 mcg/kg of milk, most in the range of 100 to 500 mcg/kg of milk. Samples with negative odor tests contained concentrations in the range of 0.98 to about 20.23 mcg/kg of milk. In one woman who donated 3 samples, the highest concentration of 71 mcg/kg occurred at 1.5 hours after ingestion, with concentrations of 1 mcg/kg before ingestion and 15 mcg/kg at 9.5 hours after ingestion.[10]

Infant Levels.

Relevant published information was not found as of the revision date.

Effects in Breastfed Infants:

Nursing mothers who were participating in an experiment on the excretion of 1,8-cineole (eucalyptol) in breastmilk took a 100 mg capsule of 1,8-cineole orally. Although instructed not to, 12 mothers breastfed their infants during the experiment. Mothers reported that none of their infants refused their milk or breastfed less than usual. Two mothers felt that their infants were more agitated a few hours after breastfeeding. A third mother reported that the infant stopped nursing from time to time and "looked puzzled", but resumed nursing. Upon repeating the experiment 6 weeks later, the infant did not react in an unusual way during breastfeeding.[10]

Possible Effects on Lactation:

In an old uncontrolled, nonblinded case series, Agnus castus oligoplex (Madaus [Germany]) was used to increase lactation. One hundred twenty-five hospitalized postpartum mothers were given the product, which was obtained from the seed of the chaste tree, in a dosage of 30 drops 3 times a day. In cases with poor response the dose was increased to 30 and 50 drops a day. Of the 125 mothers, 100 responded and left the hospital nursing their infants. Of these, 61% nursed completely, and 39% only partially. Most of the latter were primiparous women or women who had not nursed their first child. The drug reportedly lost its effectiveness over time.[11] The methodology used in this paper does not meet current standards and cannot be considered as proof of a galactogogue effects of chasteberry.

A nonrandomized, partially blinded study compared a chasteberry preparation (Agnolyt, Madaus [Germany]) 15 drops 3 times daily to one tablet of thiamine 3 times daily in postpartum mothers. Milk production was measured by the average change in weight of infants of 353 mothers treated with chasteberry, 102 cases were treated with thiamine, and 362 untreated patients served as controls. No difference in milk production was noted until about 14 days postpartum. After that time, the mothers who received chasteberry had greater milk production than those in the other groups. The effect appeared to be greater in patients with cesarean section or complications such as fever.[12] The methodology used in this study does not meet current standards and cannot be considered as proof of a galactogogue effects of chasteberry.

A double-blind study of 52 women with hyperprolactinemia compared 20 mg daily of a chasteberry preparation (Strotan, Stroschein Pharma [Germany]) to placebo. After 3 months of therapy, the prolactin response to intravenous thyrotropin releasing hormone was reduced and menstrual irregularities were reduced in the subjects taking chasteberry.[13]

In an open study of 20 healthy males, a special Agnus castusextract(BP1095E1, equivalent to 40 mgextractof chasteberry) was studied in doses of 120 mg, 240 mg and 480 mg daily in 3 divided doses. Each subject received placebo and each of the doses for 14 days, followed by 1 drug-free week. Total prolactin secretion was measured on the last day of each study period. Following stimulation by thyrotropin releasing hormone, the 120 mg dose increased serum prolactin by an average of about 16% and the 480 mg dose decreased prolactin by an average of about 10%; the 240 mg dose was approximately neutral with respect to placebo.[14]

A randomized study compared chasteberryextract40 mg daily (Agnucaston, Biomeks [Germany]) to bromocriptine 2.5 mg twice daily in 2 groups of 40 women. One group had mild hyperprolactinemia and the other had cyclic mastalgia. After 3 months of treatment, serum prolactin on day 3 to 5 of the menstrual cycle decreased by an average of 44% to 47% in all groups. No statistical difference was found between the 2 treatments in their prolactin-lowering effect.[15]

An 18-year old woman with amenorrhea, galactorrhea, and an elevated serum prolactin caused by a microprolactinoma began taking 15 drops of a chasteberry preparation containing 9 grams of chasteberry tincture per 100 grams of solution (Agnolyt, Madaus [Germany]) each morning. After 3 months her menstrual cycle had normalized, galactorrhea had ceased, and serum prolactin had decreased by 27% (although still elevated).[16]


1. Wuttke W, Jarry H, Christoffel V, Spengler B, Seidlova-Wuttke D. Chaste tree (Vitex agnus-castus)--pharmacology and clinical indications. Phytomedicine. 2003;10:348-57. PMID:12809367
2. Dennehy CE. The use of herbs and dietary supplements in gynecology: an evidence-based review. J Midwifery Womens Health. 2006;51:402-9. PMID:17081929
3. Kress D, Thanner E. [Treatment of mastopathy: the lowest possible risk]. Med Klin. 1981;76:566-7. PMID:7345363
4. Yarnell E . Botanical medicine in pregnancy and lactation. Altern Complement Ther. 1997;3 (April):93-100.
5. Scott CR, Jacobson H. A selection of international nutritional and herbal remedies for breastfeeding concerns. Midwifery Today Int Midwife. 2005;75:38-9. PMID:16320878
6. Jackson PC. Complementary and alternative methods of increasing breast milk supply for lactating mothers of infants in the NICU. Neonatal Netw. 2010;29:225-30. PMID:20630837
7. The Academy of Breastfeeding Medicine Protocol Committee. ABM clinical protocol #9: use of galactogogues in initiating or augmenting the rate of maternal milk secretion (First revision January 2011). Breastfeed Med. 2011;6:41-9 . PMID:21332371
8. Daniele C, Thompson Coon J, Pittler MH, Ernst E . Vitex agnus castus: a systematic review of adverse events. Drug Saf. 2005;28:319-32. PMID:15783241
9. Roemheld-Hamm B. Chasteberry. Am Fam Physician. 2005;72:821-4. PMID:16156340
10. Kirsch F, Beauchamp J, Buettner A. Time-dependent aroma changes in breast milk after oral intake of a pharmacological preparation containing 1,8-cineole. Clin Nutr. 2012. PMID:22405404
11. Noack M. [Our experience with Agnus castus oligoplex for increasing lactation]. Dtsch Med Wochenschr. 1943;69:204-6.
12. Mohr H. [Clinical investigations of means to increase lactation]. Dtsch Med Wschr. 1954;79:1513-6 . PMID:3220106
13. Milewicz A, Gejdel E, Sworen H et al. [Vitex agnus castusextractin the treatment of luteal phase defects due to latent hyperprolactinemia. Results of a randomized placebo-controlled double-blind study]. Arzneimittelforschung. 1993;43:752-6. PMID:8369008
14. Merz PG, Gorkow C, Schrodter A et al. The effects of a special Agnus castusextract(BP1095E1) on prolactin secretion in healthy male subjects. Exp Clin Endocrinol Diabetes. 1996;104:447-53. PMID:9021345
15. Kilicdag EB, Tarim E, Bagis T et al. Fructus agni casti and bromocriptine for treatment of hyperprolactinemia and mastalgia. Int J Gynaecol Obstet. 2004;85:292-3. PMID:15145274
16. Gallagher J, Lynch FW, Barragry J . A prolactinoma masked by a herbal remedy. Eur J Obstet Gynecol Reprod Biol. 2008;137:257-8. PMID:17298863

Substance Identification:

Substance Name:


Scientific Name:

Vitex agnus-castus

CAS Registry Number:


Drug Class:

  • Complementary Therapies

  • Phytotherapy

  • Plants, Medicinal

  • Administrative Information:

    LactMed Record Number:


    Last Revision Date:

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